More than a year out from Election Day, all sorts of Republicans are making a point of keeping themselves in the national spotlight, stoking speculation that they're positioning themselves as potential running mates for the eventual GOP presidential nominee.

It's too early to know who's really interested and who's just savoring a little extra attention. But it's clear there is no shortage of ambitious Republicans.

Indiana Gov. Mitch Daniels has a new book out. Florida's Sen. Marco Rubio and South Carolina Gov. Nikki Haley also are writing books. Virginia Gov. Bob McDonnell raised eyebrows by speaking in politically important New Hampshire, Rubio and New Jersey Gov. Chris Christie by popping up at the Reagan Presidential Library in California.

And a number of Republicans are stepping forward to endorse one GOP presidential candidate or another: former Minnesota Gov. Tim Pawlenty, who dropped out of the presidential race in August, has been campaigning for Mitt Romney. Nevada Gov. Brian Sandoval came out for Texas Gov. Rick Perry. So did Louisiana Gov. Bobby Jindal.

Then there are less typical overtures: Haley invited GOP presidential contenders Michele Bachmann and Newt Gingrich over to the governor's mansion for sleepovers.

Joel Goldstein, a professor at St. Louis University School of Law and an expert on vice presidents, says prominent Republicans may have "multiple agendas" as they maneuver for the spotlight, extending well beyond the GOP ticket in 2012.

"If you're on the short list for vice president, it enhances your position in your state and maybe you end up in the Cabinet or in a position to run in 2016," Goldstein said. "It elevates your stature. If you're left out of the discussion, then people wonder what's wrong with you."

For the most part, Republicans have demurred when asked if they're interested in the vice presidential slot – it's considered unseemly to actively campaign for the job. But most leave themselves plenty of wiggle room.

"There's no answer to this question," Daniels said when the vice president's job came up while he was promoting his book. He said he'd have to consult his family, which earlier vetoed the idea of him running for president.

Meg Whitman, the businesswoman who lost a bid for California governor in November, last summer said that if Romney wins, "I'd be happy to do almost anything he wanted me to do."

Sen. John Thune of South Dakota this summer didn't rule out any options and said he wanted to put his skill set "to its highest and best use."

Who's not giving much thought yet to the veepstakes? The top-tier Republican presidential candidates; they're too busy trying to secure the nomination. (And hoping Christie sticks to his word and doesn't run for president himself.)

But it can be smart electoral politics to stroke local politicians as potential veep candidates, so the topic keeps coming up.

Romney has talked up McDonnell, Rubio and Christie as potential veep material. Bachmann's spoken highly of Rubio and South Carolina Sen. Jim DeMint. A number of the GOP candidates have said their current rivals could be potential running mates.

Perry went so far as to suggest the ideal candidate would be a blend of Gingrich and businessman Herman Cain.

Cain, for his part, dismissed all the vice presidential speculation as a game.

Early veepstakes speculation always is something of a political parlor game. But the unofficial tryout period also can serve a useful purpose, says Democrat Dick Harpootlian, who's been watching Haley's activities from his perch as chairman of the state Democratic Party in South Carolina.

Harpootlian says the early months of the campaign can be a time for potential vice presidential candidates to demonstrate "their ability to walk, talk and chew gum at the same time." John McCain's surprise selection of little-known Alaska Gov. Sarah Palin in 2008, he said, "left the Republican Party, at least the elders in it, astounded at how wrong things can go when you pick somebody out of obscurity."

GOP strategist Rich Galen said politicians like to be in the mix as potential vice presidential candidates, even if it's just to increase their stock for a future political campaign.

"You want to be mentioned," he said.

But not all attention is the right kind. Haley found herself owning up to a "poor choice of words" earlier this month after she called a female reporter a "little girl" when the woman wrote a story that detailed at least $127,000 in state spending on a European economic development trip.